It all depends on what you want and need.
For me, it was to control the Factors I had in the FX-Loop of a Rack Amp Modeller and I racked the Factors…. so please bear in mind that I was looking to control a few things other than the Factors.
I have had these in this order….
1. Rocktron MIDIMate – quite nice and compact, but you can not set TapTempo on the Factors (and other devices) not the easiest to program. You can have a combination of PC and Midi CC
2. Ground Control Pro – Easiest one to program IMHO, You can have a combination of PC and Midi CC, but the MIDI CC could only send MIDI CCs on one channel (might not be much of an issue) Really liked this controller and best bang for buck IMO. There is a windows editor you can use to program it, but I never used it as the unit was sooo easy to program.
3. Fractal MFC-101 – Dedicated to my modeller and VERY flexible…but due to the flexibility it is more complicated to program. there is currently no computer editor…Looks expensive, but comparing the functionality and others it is actually well priced.
I am sticking with the MFC-101, it is currently controlling my Modeller, Space and Eclipse in my rack….very happy.
The others that I have seen get a lot of love, but not used personally so can not really comment on….
Behringer FCB1010 with the UNO chipset – very cheap and well regarded
Liquid Foor Jr.
Gordius
G-Lab make some interesting stuff
